The Lebanese prime minister Saad Hariri has unexpectedly resigned during a trip to Saudi Arabia, warning his life was in danger.
Speaking in the nation's capital, Riyadh, he said the climate in Lebanon was like it was before his father, prime minister Rafik Hariri, was assassinated in 2005.
He also attacked both Iran and their allies in Lebanon, the Shia Muslim militant group Hezbollah.
He accused them of meddling in Arab affairs and said that "Iran's arms in the region will be cut off".
Lebanon is largely divided between those loyal to Saudi Arabia, led by Sunni Muslim Mr Hariri, and those loyal to Iran and Hezbollah.
The prime minister's resignation will raise tensions in the country and has thrown its political future into uncertainty.
Mr Hariri's comments come after the US imposed new sanctions on Hezbollah that many people in Lebanon fear will damage the country's economy.
Mr Hairi said Hezbollah's policies have put Lebanon "in the eye of the storm".
"When I took office, I promised you that I would seek to unite the Lebanese, end political division and establish the principle of self-sufficiency, but I have been unable to do so," he said.
"Despite my efforts, Iran continues to abuse Lebanon."
He said: "We are living in a climate similar to the atmosphere that prevailed before the assassination of martyr Rafik al-Hariri. I have sensed what is being plotted covertly to target my life."
Mr Hariri was appointed prime minister in late 2016 and was leader of a 30-member national unity cabinet that included Hezbollah.
President Michel Aoun, who took office in October 2016, is a close ally of the militant group.
He was elected after Mr Hariri endorsed him for president, based on an agreement that he would make him as prime minister.
The government have managed to avoid the country being embroiled in the worst of the conflict taking place in neighbouring Syria.
In a statement the president's office said they had been informed of the resignation in a phone call.
They said they were now waiting for Mr Hariri to return to Lebanon to clarify the circumstances of his resignation and proceed accordingly.